360, ps3 ,wii ,and pc wise and only exclusives (no games can be used for a system if it is on another system).

Now go

360- HALO REACH probably

PS3- GOD OF WAR III or LITTLE BIG PLANET 2

WII- SUPER MARIO GALAXY 2

PC- STARCRAFT 2

PS3: FFXIII or Heavy Rain

I can't really speak about the 360 and I haven't played my Wii a lot this year.

I don't really know... I don't like a whole lot of exclusives I've played that much, and I've only played 1 for most consoles... For example ME2, Red Dead Redemption and FFXIII doesn't count here :(

PC: Starcraft 2 (Best exclusive imo)
Xbox 360: Lara Croft: Guardian of Light (won't be exclusive but currently is).
Wii: Mario Galaxy 2 (Not extremely fond of it, but can't think of another)
PS3: Heavy Rain (Ditto)
PSP: Valkyria Chronicles II (Only played the demo, but I like it more than peacewalker)
DS: Dragon Quest IX

I'll post my results after Halo Reach comes out

PS3: God of war 3

360: Mass effect 2

Wii: Super Mario Galaxy 2

Multiplat: Red Dead Redemption.

PS3: Uncharted 2

Wii: Super Mario Galaxy 2

360: Mass Effect 2

PSP: TBA when third birthday comes out

DS: The world ends with you

PC: Witcher

PS3 - God of War III

360 -  Mass Effect II

Wii - Super Mario Galaxy 2

DS - ...I haven't actually bought any DS games this year.

PC - Ditto.

PS3 - Heavy Rain (8.7/10 --- very fresh game and fun to play)

Wii - SMG2 (9.3/10 -- best mario platformer)

PC - Mass Effect 2 (9.2/10 -- amazing WRPG)

DS - DQIX (8.9/10 -- best original DS RPG behind TWEWY and SMT:Devil Survivor)

Multiplat - FFXIII (9.7/10 -- Best game of gen behind MGS4)

____________

so lol'ingly enough, despite my Wii "hate" it has the best exclusive this year so far LAWL!